This invention relates to a very high brisance metal powder explosive and more particularly, to a high energy, high energy-rate-release insensitive high-explosive composition.
The military constantly seeks more powerfully explosive warheads. The addition of aluminum to increase the performance of explosives was patented by Roth in 1900 (G. Roth, German patent 172,327 (1900)). According to Lheure (L. Lheure, MP 12,125(1903-1904)), the leader of Austria in 1901 proposed to the French government the use of aluminum in explosives. Historically, aluminum containing explosives, or aluminized explosive compositions, such as ammonal (ammonium nitrate/trinitrotoluene/aluminum powder/charcoal 65%/15%/17%/3%) was used by the military since World War I, in particular by Austrians, Germans, and to lesser extent by the French. Notwithstanding satisfactory performance of aluminized explosives, they were not used much as long as the quantity of aluminum on the market was limited and its cost much higher than of any other ingredient in the explosive composition. When these drawbacks were overcome sometime after WWI, more and more aluminized explosives started to be used not only for military purposes but also as industrial explosives. In World War II, aluminized explosive compositions were widely used by all the belligerent nations for incendiary and enhanced blast bombs especially in underwater ammunitions such as mines, torpedoes, depth charges, etc., where they were found to be most effective. In the 1970's, 1990's, and 2000's there was a renewed interest in developing metalized CHON (carbon-hydrogen-oxygen-nitrogen) explosive compositions using other metal powder additives such as magnesium, silicon, boron, and other high oxidation-reaction-heat metals. The action of aluminum in explosives was investigated by many researchers and it had been claimed that aluminum does not take part in the actual detonation but reacted immediately afterward with the products of explosion such as CO2 and H2O. For illustration:2Al+3CO2→Al2O3,+3CO+196 kcal/mol2Al+3H2O→Al2O3+,3H2,+226 kcal/mol
The large amounts of heat liberated by these reactions maintain a high pressure of explosion for a longer period of time than would be obtained without aluminum. The pressure-time curves of explosions containing aluminum do not have such high “peaks” as do the corresponding non-aluminized explosives but the pressures remain high, lasting 2-3 times as long. Researchers have shown that aluminum reacts not only with oxygen but also with nitrogen forming a nitride. For illustration:Al+N→AlN+80 kcal/mol
This means that it would not be necessary to make aluminized explosives with a positive oxygen balance, as was done prior and during WWI, but it is better to maintain some negative balance. Currently, industry and the military have used aluminized/metalized explosives which are comprised of solid, or more or less solid, particles of explosive substances and/or of solid particles of metals. The explosives of this invention explore use of hollow type particles instead. Better capabilities are proposed for explosives of this invention using hollow type particles.